Referring to FIG. 1, a diagram of a conventional storage area network (SAN) installation 10 is shown. The SAN installation 10 includes a number of disk drives 12, a storage unit/controller 14, a storage area network (SAN) 16, a number of host/servers 18 and a router or local area network (LAN) 20 for external access to the storage system. The storage area network 16 can be implemented using SCSI or fiber channel (FC) protocols. However, SCSI and FC buses are distance limited. Constructing SANs to span a medium area network (MAN) or even a wide area network (WAN) is not viable with SCSI or FC busses. The servers 18 can be a bottleneck for several operations because all accesses must go through the servers 18. Although the servers 18 provide a useful necessary function by isolating the SAN 16 from the outside network, even with additional servers 18, a throughput constraint is introduced as the servers 18 direct all traffic and perform protocol conversions.
Internet SCSI and iFC are protocols for encapsulating (establishing and transporting) SCSI and FC commands across an internet protocol (IP) network instead of a direct SCSI or FC compatible cable. By using iSCSI or iFC, storage management software that was originally written for SCSI or FC can be used to make a remote disk or tape drive on a network operate like a local disk. The network can be a local area network such as ethernet or even the internet.
Internet SCSI (iSCSI) and iFC target rates of 1 Gbps and 10 Gbps. Current TCP/IP designs to support iSCSI and iFC can be slow and power hungry. Conventional designs use firmware based TCP/IP stacks, with additional software for iSCSI/iFC stacks, and additional Ethernet MAC hardware components. The firmware based TCP/IP stacks are executed on expensive network or high end processors. The conventional designs can be expensive, require a large chip count, require high power, and provide inadequate bandwidth (i.e., not scalable to 10 Gbps).